Prove the following identity:
(1+tan2A)+(1+cot2A)=(1sin2A−sin4A)(1 + \tan^2 A) + (1 + \cot^2 A) = \Big(\dfrac{1}{\sin^2 A - \sin^4 A}\Big)(1+tan2A)+(1+cot2A)=(sin2A−sin4A1)
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Solving L.H.S. of the equation :
⇒(1+tan2A)+(1+cot2A)⇒sec2A+cosec2A⇒1cos2A+1sin2A⇒sin2A+cos2Acos2Asin2A⇒1cos2Asin2A⇒1(1−sin2A)sin2A⇒1sin2A−sin4A.\Rightarrow (1 + \tan^2 A) + (1 + \cot^2 A) \\[1em] \Rightarrow \sec^2 A + \cosec^2 A \\[1em] \Rightarrow \dfrac{1}{\cos^2 A} + \dfrac{1}{\sin^2 A} \\[1em] \Rightarrow \dfrac{\sin^2 A + \cos^2 A}{\cos^2 A \sin^2 A} \\[1em] \Rightarrow \dfrac{1}{\cos^2 A \sin^2 A} \\[1em] \Rightarrow \dfrac{1}{(1 - \sin^2 A) \sin^2 A} \\[1em] \Rightarrow \dfrac{1}{\sin^2 A - \sin^4 A} .⇒(1+tan2A)+(1+cot2A)⇒sec2A+cosec2A⇒cos2A1+sin2A1⇒cos2Asin2Asin2A+cos2A⇒cos2Asin2A1⇒(1−sin2A)sin2A1⇒sin2A−sin4A1.
Since, L.H.S. = R.H.S.
Hence, proved that (1+tan2A)+(1+cot2A)=(1sin2A−sin4A)(1 + \tan^2 A) + (1 + \cot^2 A) = \Big(\dfrac{1}{\sin^2 A - \sin^4 A}\Big)(1+tan2A)+(1+cot2A)=(sin2A−sin4A1).
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(cosA1+sinA)+tanA=secA\Big(\dfrac{\cos A}{1 + \sin A}\Big) + \tan A = \sec A(1+sinAcosA)+tanA=secA
(sinθ+cosθ)(tanθ+cotθ)=secθ+cosecθ(\sin \theta + \cos \theta)(\tan \theta + \cot \theta) = \sec \theta + \cosec \theta(sinθ+cosθ)(tanθ+cotθ)=secθ+cosecθ
sec2A+cosec2A=tanA+cotA\sqrt{\sec^2 A + \cosec^2 A} = \tan A + \cot Asec2A+cosec2A=tanA+cotA
(tan A + cot A)(cosec A - sin A)(sec A - cos A) = 1